Comment 3 for bug 1675796

The issue is that for a single arm SF, the OVS agent (packet re-classifier in SFC Proxy) needs to distinguish forward traffic from reverse traffic that is returned from the SF.

The only way to do that is to match on the n-tuple fields of the packet such as source IP prefix.
If the flow classifier only has the logical-source-port as in your example the ovs is cannot do that.

Try adding a source IP prefix to the flow classifiers fc1 and fc2.